Electrocatalysis and detection of nitrite on a reduced graphene/Pd nanocomposite modified glassy carbon electrode

An electrochemical reduced graphene oxide/palladium (ERGO-Pd) nanocomposite modified glassy carbon (GC) electrode was fabricated by electrochemical reduction of GO and electrochemical deposition of Pd nanoparticles, respectively. Raman spectra indicate the GO can be successfully reduced to ERGO. SEM displays a high density of Pd nanoparticles loading on the surface of ERGO with a diameter of 50–100 nm. The electrode exhibits enhanced electrocatalytic behavior to the oxidation of nitrite compared to the GO and ERGO modified GC electrode. The effects of solution pH and amount of Pd deposition onto the ERGO-Pd modified GC electrode were investigated and discussed. Under the optimal conditions, the ERGO-Pd modified GC electrode can be used to determine nitrite concentration in a wide linear range of 0.04 and 108 μM and a limit of detection of 15.64 nM. The sensitivity of the electrode was 7.672 μA μM−1 cm−2. It also shows good storage stability.